I've found numerous posts on stackoverflow on how to store user passwords. However, I need to know what is the best way to store a password that my application needs to communicate with another application via the web? Currently, our web app needs to transmit data to a remote website. To upload the data, our web app reads the password from a text file and creates the header with payloads and submits via https.
This password in plain text on the file system is the issue. Is there any way to store the password more securely?
This is a linux os and the application is written in python and is not compiled.
Further clarification:
There are no users involved in this process at all. The password stored in the file system is used by the other web app to authenticate the web app that is making the request. To put it in the words of a commenter below:
"In this case, the application is the client to another remote application."
From the question it seems you need to store password in such a way, that it can be read and used in an automated transaction with another site. You could encrypt the password and store it encrypted in the file, then decrypt it using a key stored elsewhere in your system before using it. This makes difficulties to someone that gets access to the file from using the password, as they now have to find the key and encryption algorithm used, so they can decrypt it.
As defense, more lesser defense is always better than one strong defense that fails when breached. Moreover, I would also secure the file containing the password, rather than the password itself. Configure your webserver to disable possibility to serve the file containing the password, and try to set the process needing the file to run under a separate account, so you can restrict the access to the file to account running the process and admin accounts only.
I don't think you will find a foolproof way to do this. I would suggest a combination of things to achieve 'security by obscurity':
store the password file on a different computer than the one which will use it
store the file path in a separate config file on the app nachine
use permissions to limit access to the config and password files to your process only
audit file access if your system allows it (keep a log of who touched the files)
give the folders and files innocuous names (/usr/joe/kittens.txt?)
block physical access to the computer(s) (offsite hosting, or locked closet, or something)
You can use a two-way key encryption algorithms like RSA,
The password is stored encrypted (by a key, which is stored in the user's brain) on the filesystem, but to decode the password, the user must enter the key.
At the very least you should use permissions (if you are on a filesystem which supports them) to ensure that you are the only one able to read the file.
In addition, if your app is compiled, it would not be too difficult to encrypt the password with a hard-coded passphrase. If the code is not compiled this method wouldn't really be helpful, as a would-be attacker could just read the source and determine the encryption.
You can store it as a result of hash algorithm, this is one way algorithm (eg. MD5 or SHA). On authentication you calc MD5 of password typed by user and checking equality with your stored MD5 password hash for this user. If is equal password is ok.
For more information about hasing algorithms you can visit:
http://en.wikipedia.org/wiki/Secure_Hash_Algorithm
http://en.wikipedia.org/wiki/MD5
Is your web application hosted on a farm? If not then a technology such as DPAPI will allow you to encrypt the password so that it can only be decrypted on the machine it was encrypted on.
From memory there can be problems with using it on a web farm though, as you need to go and re-encrypt the value for each server.
If it is a web farm then you probably want to use some form of RSA encryption as has been suggested in other answers.
EDIT: DPAPI is only good if you are hosting on windows of course...
Protecting the Automatic Logon Password
The LsaStorePrivateData function can be used by server applications to store client and machine passwords.
Windows only
I don't think you are understanding the answers provided. You don't ever store a plain-text password anywhere, nor do you transmit it to another device.
You wrote: Sorry, but the issue is storing a
password on the file system... This
password is needed to authenticate by
the other web app.
You can't count on file system protections to keep plain-text safe which is why others have responded that you need SHA or similar. If you think that a hashed password can't be sufficient for authentication, you don't understand the relevant algorithm:
get password P from user
store encrypted (e.g. salted hash)
password Q someplace relatively
secure
forget P (even clear the buffer you
used to read it)
send Q to remote host H
H gets password P' from user when
needed
H computes Q' from P', compares Q'
to Q for equality
Related
I have a web app that uses known username and password combinations to login to external servers. There are multiple username/password combinations used for different services. Right now, they are essentially "hard-coded" into the website code, but, I would like to move this information off the code base for better security.
My initial thought is to store this data in the database which is used to support the website. I want to store it in a way that it is not easily "hackable" (i.e. I'm not going to store it as plain text or as a MD5 hash). Should I follow the same format that I use to store the website user's passwords, where I use a random number generator to create SALT for each password and then store the password as hashed combination of the password and SALT, or would this be overkill?
Generally, storing passwords in the application code is always a bad idea. Moving it outside the code has many advantages including security.
Now storing it either in DB or Configuration Files is a choice you have to take depending on your application.
For full security you should never store passwords in retrievable form. But to login to a external server as in your case, you need to get the actual plain text password, so one way hash will not work for you.
In our product we deal with such situation by using 2 Way SSL Certificates. It is very secure and there is no need to store the passwords.
But if you really need to store the passwords, then I will suggest to use configuration file and let your application read it. You can encrypt the passwords stored in the configuration files (Encrypting the passwords stored in the configuration file will again bring you back to the same question of how to protect the key). The access to the configuration file should be restricted (in Unix, 600 File Permission).
Alternatively, if your web application is Java, then you can consider using JNDI.
After more research, I've decided at this point to follow the ideas here:
Encrypt a Column of Data - SQL Server | Microsoft Docs
...and encrypt/decrypt on the DB inside a Stored Procedure.
I configured msmtp with my gmail account.
I obviously want to avoid writing my password in plaintext format in the config file.
Luckily enough msmtp offer the option passwordeval which can be used to obtain the password from the output of an an executable.
The question is: how should I use it?
I found here the following suggestion:
passwordeval gpg -d /some/path/to/.msmtp.password.gpg
That doesn't make much sense to me: if someone is able to access my config file he will certainly manage to run such a command and obtain the password from gpg.
So I believe I'm left with the only option of obfuscating the password within the binary executable even if I read almost everywhere that this is bad!
My impossible-to-hack implementation is: if the sendmail process is running output the correct pass, otherwise give a fake pass.
Your suggestions?
Other (more secure) tricks different from storing the pass in the binary file?
From Sukima's comment:
The reason gpg -d works is because it requires the private key of the person the file is encrypted to. So just placing that encrypted file in the public it is still encrypted an only one person (the one with the secret key) can decrypt it. It is assumed that the secret key is locked up on the user's machine and not leaked. It also assumes that they have not setup any agents which cache the unlock password while a hacker has direct access to the same machine. All of which is highly unlikely in 99% of all attacks.
There is not a standard solution on how to save credentials with the constraint of
having to use the credentials in plain text later
and in an unattended way
on a system which is not completely controlled by you (if it is you just set appropriate rights on the files holding the secrets)
You have several solutions, none solves perfectly your problem:
encrypt your credentials in a symmetric way: you need to input the key to decrypt them
encrypt in an asymmetric way: you need to provide your private key, which must be stored somewhere (unattended approach) or keyed in
obfuscate: as you mention, this only protects from some population
get it from somewhere else - you need to identify a way or another your system
You need to take into account which risk is acceptable and go from there.
I am trying to find a technique to encrypt and decrypt a file in a program without hard coding the password into the program and without asking the user for it.
It would be nice if I could also decrypt the file from another program that I also am writing.
So far I haven't had much luck finding a good technique that looks secure enough for my liking.
I'm writing this in c# but the language isn't important I just need someone to point me in the right direction towards an algorithm/technique.
This is a recurring problem with no safe real solution. If you want to be able to encrypt/decrypt something safely, you need a key. Your program needs to know that key. If the key is stored, somebody else can find it and use it to access your encrypted data.
Think of it like this: If your program should be able to access the encrypted data without hard coding the key into the program and without asking the key from the user, then why can't any other program do the same and acquire the encrypted data?
I think you need to define the problem further before you are ready to talk about how to code it.
Specifically, who should be able to decrypt the data? And what technique would you use to prevent others from doing it.
As it stands, the question may was well be "I'd like a lock on my door that doesn't require a key." The statement hasn't really defined the goal with enough clarity.
Put a web resource up with the password on it, and have the code request that web resource. Of course, to do this securely involves SSL and a webhost, but it fits your needs.
If your program features user accounts with their own passwords, you could do something like:
Set up a users table containing a column for storing an encrypted copy of the program-wide password.
Encrypt a copy of the program-wide password in each user's account using the user's password as the key.
When the user logs in, the system password is decrypted using their password and stored as a session-length cookie (SSL only) on their browser.
In this way, each user can get a copy of the system password silently in the background.
HOWEVER, this approach has some serious drawbacks.
First, the system password becomes no more secure than the WEAKEST user password. If Bob from Accounting sets his password to "password123", then that can be used to retrieve a copy of the system password.
Second, an attentive attacker will notice that cookie contains the system password, and then you're screwed.
You could obviate that by actually storing the decrypted password on a third machine accessed via SSL, then retrieve it for each transaction based on the user's session ID; but this would mean if the third server goes down for any reason, your entire system is down. It would also impose performance penalties, and your data server's security would depend on the password server's security.
And after all that convolution, in the end there's no really good solution; you just have to either prompt them for the password or store it on the server itself and lock the server down as tight as you can.
In cryptography the strength of the encryption scheme is the function of secrecy and strength of the key. This means that the key must be secret (i.e. not accessible to the attacker). Now, if there key is not in user's hand and not in the application code, where it is? And how secret it is?
So you need to re-think your task. Maybe good obfuscation of the key will drive away most not-very-skilled attackers. The simplest way to obfuscate the key is to use some text phrase of your program as a key. This makes operations with the key less obvious for an occasional lurker (professionals know different ways to find the encryption keys in the application).
Maybe the best answer could be a password generated by some means (like the size of a file or any other fixed value in the system). So you store in code the way to obtain the password rather than the password itself.
I've currently thought about a web-driven password database with multiple accounts and the login/passwords stored in a Database engine like MySQL or Oracle. Each password should only be available to some of the users:
User A logs in, creates a new login information and ticks some checkboxes to make this information available to User B and User C. User D and E should not see it.
My first thoughts:
The passwords are stored encrypted in the database.
The main problem here is of course, if you have access to the server you can take a look a the script and detect the decryption algorithm with enables you to de-crypt all the stored passwords at once.
So I thought, each user gets a master password to the password tool which is part of the encryption/decryption algorithm (user enters this master password and the logs in with his own credentials). This had the benefit that a third person could not simply take a look at the scripts to see how they are decrypted exactly as he had to know the master password. But of course it's still possible for users with very limited access to decrypt all of the passwords as they know the master password.
So basically my question is: how is it possible to have a webbased multiple user password database which is not just cracked easily by looking at the plain sources, if someone gets access to the server? Is it possible to make the decryption somehow dependent on the user logins which may officially see the password?
Thanks for any hints on this!
Notice to make things more clear:
It's intended to be a password database where login credentials for different applications are stored and users can log in and see what credentials they have to use for these applications. Like password manager tools like 1Password and so on. It's just a simple lookup table with username/password, it should not insert or interact with 3rd-party applications.
The solution is here:
Is it possible to have encryption with multiple private keys (PHP)?
Use a one way hashing algorithm like MD5 or SHA-1 (or some of its stronger variants). This way, there will be no way to reverse engineer stored passwords.
Have you looked at any products like Passwordstate? All the passwords are encrypted within the database, they can be shared amongst multiple people, all the pages are obfuscated for further protection, and it integrates with Active Directory for authentication.
There's a free 10 user license if you want to check it out.
Situation 1 - Connecting the server to the database:
Its always said that passwords should not be stored in plain text, however to connect to the mysql database requires the password, in plain text it seems... I'm guessing the best solution to this is to store it in an encrypted form, decrypt it in my app as needed and then erase it from memory (SecureZeroMemory in windows I guess so the compiler cant optimise it out).
Situation 2 - Users logging into the server from a remote computer:
As for users passwords my plan is to never actually store the original password at all.
Instead I will store a randomly generated "salt", for each user, prefix there password with it then hash it, which seems to be a relatively common way. However I don't have an SSL connection available at this point, so I'm guessing the plain text passwords could be intercepted, what's a good solution to this?
What are good algorithms (links to C/C++ implementations would be handy as well if you have them) for doing this, a look on the net comes up with 100's of them?
EDIT:
If I got SSL, would the following be secure (assuming a strong hash algorithm is used), or should a different method be used?
Client requests salt for a user name
Client prefixes password with salt, then hashes it before sending the hash to the server
Server compares hash recieved to the one on the server for that user name
Connecting the server to the database
Just storing the database password in the server - encrypted or not - is a bad idea. It is obvious storing it in plain text, of course. And if you just store it encrypted, the server still needs the key to decode it. It is usually not very hard to find the key in the server code. The best solution is to let the user starting the server enter the password and store it nowhere. Alternatively - and probably even better - you can store all sensitive information - for example database users, passwords, and so on - encrypted and let the user starting the server enter a master key to decrypt this information.
Connecting a user to the server
This is really a hard problem and easy to mess up. A quote from this great article article on the topic I absolutely recommend reading.
No, really. Use someone else’s password system. Don’t build your own.
A good solution might be using the Secure Remote Password Protocol.
You are correct that if you're not using SSL then the passwords can be intercepted.
It is common practice to never decrypt a user's password, so keep it stored hashed with a salt and when the user types in their password you will add the salt and hash it, comparing it with the stored, hashed password. This will allow you to never have the decrypted version of the password every.
You really should look into securing the connection so that the password is secure when the user types it in.
Update to answer edited question:
If you have the communication secured using SSL you can still use any number of extra measures of security you like including hashing the password. As added security it is a good idea to remember that the password you store should be stored hashed with a salt. That salt should be kept safe and never be accessible anywhere except by your application. This way when the user submits the password you just add the salt and hash and you compare that version with the stored version.
Situation 1 - Connecting the server to the database
There isn't an easy answer here. In order to connect, the server needs the password (or symmetric key, or private key or whatever). It must get it either from the disk or some external means (like an administrator typing it at startup). Adding some indirection, such as encrypting all the sensitive stuff under a master password, can add some convenience but otherwise doesn't change the situation.
Typically, it is fine to put the password or key in a file on a server. If you do this, make sure to set the permissions on the file so that only the users that need it have access to it. This is an excellent reason to have different processes on your system run as different users, and to set up separate roles/accounts and passwords for each.
Situation 2 - Users logging into the server from a remote computer
You are headed in the right direction here, I think. What it sounds like you're asking for is a secure authentication protocol. You want one that provides mutual authentication and prevents a man-in-the-middle attack by failing if such an attack is attempted. There are many to choose from of course.
It is also worth mulling whether your authentication should operate based on "something you know" (passwords) or "something you have" (public/private keys). Assuming based on your question that what we're looking for is passwords, two that I like are SRP and Kerberos.
SRP was mentioned earlier, and that doesn't get nearly the attention it deserves. SRP has the advantage that it doesn't require the server to know the password, or key, or anything that an attacker could use to gain access. If you broke into a correctly configured server using SRP and stole all the data, you'd still need to do something like a dictionary attack on each key individually before you had anything you could use to impersonate a user.
I also like Kerberos because it is supported by tons of software (I know Postgres supports it, I've only found mentions of mysql not supporting any good authentication technology) and has a system of 'tickets' that provides a single sign on capability. Kerberos needs some other technology to help strengthen its initial authentication exchange and SRP would be great for that but I'm not sure they've done that yet. Something about it making the KDC (key server) stateful I think.
Kerberos' weakness is that you have to be more wary of the server storing the keys. While it doesn't store the passwords in plaintext, it does store the keys, which are essentially hashed versions of the passwords. And while the client doesn't exactly send either the password or the key straight over when authenticating (this is a Real auth protocol after all), it does use the hashed password as the key, and so anyone else who knows the algorithm and knows the key could do the same. We say that the server stores a "password equivalent". As a result, all the manuals tell administrators to put the kerberos services on their own separate, locked-down boxes to minimize the chance of compromising their contents.
The nice thing is, once you settle on a strong authentication exchange, other good things typically fall out of it for free. You end up with both parties sharing a mutual 'secret' that can be used once for the duration of the session, never sent over the wire, and can't be known by a third party. Want encryption? There's the key, all ready to go. This is exactly how SRP-secured SSL is defined in RFC 5054.
Not sure if this is what you are asking for.
But a simple PHP example using the built in sha1 function:
// Check the hashed password from the database
if (sha1($salt.$password) == $providedPassword)
{
// User is authenticated
return TRUE;
}
else
{
// User is not authenticated
return FALSE;
}
One thing you could do is also hash the password with javascript before it is sent over the wire. The question is how is the salt string shared between client and server? One possibility is to use a session variable. And then use the session variable to unhash the password afterwards on the server. This would mean that the man in the middle would need to know one other piece of info to make sense of the password. Not as secure as SSL, but perhaps an extra layer of defense against casual network sniffers.
I could also imagine a hashing scheme linked to some sort of captcha system used to salt the password on the local client before sending over the wire. The client would be providing the text for the salt string by completing the captcha. You could look it up on your end.
The main concern is the man in the middle not understanding the plain text password.
SSL should be used, but the above techniques might be useful where SSL is not possible.
Newer MySQL uses hashed password over the wire, so you don't have to worry about man-in-the-middle.
If you worry about the password stored in your configuration file, you can encrypt the configuration file with a password. However, the problem is that you have to enter a password to start your application.
I wrote a similar application over 15 years ago. Back then, PGP was my choice. I am not even sure it's still around.